Field of the Disclosure
The present disclosure relates generally to network communication and, more particularly, to network interconnection and protection used, for example, in a Dual Node Interconnect (DNI) leveraging ITU-T G.8031 and similar or related protocols.
Description of the Related Art
The following abbreviations are herewith expanded, at least some of which are referred to within the following description of the state-of-the-art and the present invention
APS Automatic Protection Switching
CCM Continuity Check Message
DNI Dual Node Interconnect
DRNI Distributed Resilient Network Interconnect
IEEE Institute of Electrical and Electronics Engineers
ITU International Telecommunication Union
LoC Loss of Continuity
MAC Media Access Control
MEG Maintenance Entity Group
MEP Maintenance End Point
OAM Operation, Administration and Maintenance
PDU Protocol Data Unit
SF Signal Fail
SF-P Signal Fail on Protection
SNC SubNetwork Connection
VID VLAN Identifier
VLAN Virtual Local Area Network
Modern communications often involve many interconnected nodes, or special purpose computing devices that receive and forward data traffic and control messages encoded in electronic form. The nodes may be connected together with other devices by, for example, fiber optic or copper cables. Each node may have a number of ports to which the cables or other transmission means are connected, so one node may be connected to many others.
Communication networks may carry data representing, for example, email, voice calls, or streaming video. A transmission traveling from source to destination may pass through many network nodes. Nodes may be, for example, bridges, switches, or routers. Networks may interconnect with other networks, hence the term “internet”, and a transmission may pass through a number of such networks.
In many instances, a dedicated circuit through the network or networks is not established for a single call or other communication between source and destination. Instead, data is divided into units sometimes called packets or frames, which are individually addressed so that non-destination nodes receiving a frame may identify a port on which to forward the frame. At their destination, the transmission units are reassembled to replicate the originally transmitted data. The process of addressing and transporting data is largely standardized, for example in protocols promulgated by the ITU or IEEE so that nodes made by a variety of manufacturers may operate in the same network. One widely-used scheme that is described in a number of protocol documents is known as Ethernet.
As network nodes and the cables or other means connecting them are subject to failure (including inadvertent disconnection), protection schemes have been worked out so that data can be re-routed to permit communications to continue while automatically circumventing the failed device or path. A description of one such scheme is set forth in a document referred to as ITU-T G.8031 (Ethernet linear protection switching).
Standard protocol documents, though comprehensive, often do not describe every situation or environment. In the case of G.8031, for example, it would be advantageous to find solutions to efficiently support protection in a DNI configuration at the interconnection of two networks.